Printing machine



Feb. 22, 1944. I w GQLLWITZER 2,342,190

' PRINTING MACHINE Filed Oct, 27, 1941 5 Sheets-Sheet 1 Feb. 22, 1944.

w. T. GOLLWITZER 2,342,190

PRINTING MACHINE Filed Oct. 27, 1941 5 Sheets-Sheet 2 Feb. 22, 1944. w. T. GOLLWITZER PRINTING MACHINE Filed 001;. 27. 1941 5 Sheets-Sheet 3 Zl/Mm 4 el/Z540 Feb. 22, 1944. w. 'r. GOLLWITZER PRINTING MACHINE Filed Oct. 27. 1941 5 Sheets-Sheet 4 III/7210 Feb. 22, 1944. w. 'r.. GOLLWl TZ ER PRINTING MACHINE Filed Oct. 27. 1941 5 Sheets-Sheet 5 Patented Feb. 22, 1944 PRINTING MACHINE Walter T. Gollwitzer, Euclid, Ohio, asslgnor to Addressograph-Multigraph Corporation, Wilmington, Del., a corporation of Delaware Application October 21, 1941, Serial No. 416,636

7 Claims.

This invention relates to printing machines and particularly to sheet separating and feeding devices for such machines.

In my United States Patent No. 2,002,773, patented May 28, 1935, I disclose a pneumatically operated device for separating sheets from a stack in which they are arranged and for successively feeding such sheets into a printing machine, and the present invention pertains to improvements upon the device disclosed in that patent.

A primary object of the invention is to prevent, by novel means and in a novel manner, the feeding of more than one sheet at a time to the machine with which the device is used, which may be a printing or other like machine.

More specifically, it is an object of the invention to insure proper separation of the sheets by a novel combination of elements functioning in a more efl'icient manner and to accomplish a better result than any of the prior art sheet separating and sheet feeding devices with which I am familiar, for the purposes and use for which the new sheet separating and sheet feeding device is intended.

Another object of the invention is to detect, by novel means and in an effective manner, the inadvertent feeding of more than one sheet at a time and to prevent the passage of such plurality of sheets to a machine with which the new sheet feeder may be used.

A further object of the invention is to so arrange the sheet separating device that it may be electrically controlled from the machine with which it is used, and an ancillary object is to utilize an electromagnetically operated one-revolution clutch for effecting operating cycles of the sheet separating device.

Still another object of the invention is to provide a novel sheet separating and sheet feeding device of simple and economical construction and which is dependable inoperation.

An additional object of the invention is to aiford a new and improved sheet separating and sheet feeding device which is especially adapted for use with the printing machine forming the subject matter of my copending application, Serial No. 416,745, filed October 17, 1941. In such a printing machine the sheets may be advanced in a particular direction through successive printing stations to have various impressions made thereon, and may then be retracted in the reverse direction to enable still other impressions to be made thereon. It is essential that the simultaneous feeding of a plurality of sheets be prevented in such an instance inasmuch as the plurality of sheets may become separated in the course of being advanced and retracted as aforesaid, causlng the several impressions which should be made on a single sheet to be distributed over two or more separate sheets. The present invention is therefore particularly designed to feed only a single sheet at a time to the printing machine.

Other and further objects of the present invention will be apparent from the following description and claims and will be understood by reference to the accompanying drawings which, by way of illustration, show a preferred embodiment and the principle thereof and what I now con-- sider to be the best mode in which I have contemplated applying that principle. Other embodiments of the invention embodying the same; or equivalent principle may be used and structural changes may be made as desired by those skilled in the art without departing from the present invention and the purview of the appended claims.

In the drawings,

Fig. 1 is an elevational view of the sheet separating and feeding device or unit, certain parts being omitted from this view for the sake of clarity;

Fig. 2 is a verticalsectional view taken on the line 2-2 on Fig. 1 and looking in the direction of the arrows;

Fig. 3 is a detail elevational view of a clamping collar shown in Fig. 2;

Fig. 4 is an elevational view looking in from the left in Fi 1;

Figs. 5 and 6 are fragmentary elevational views looking in a direction the reverse of that in which Fig. 1 is viewed (or from the right as viewed in Fig. 2)

Fig. 7 is a detail elevational view of a rocker shown in Fig. 2;

Fig. 8 is a detail plan view of a part of a clutch shown in Figs. 1 and 4;

Fig. 9 is a schematic elevational view of the clutch structure;

Fig. 10 is a vertical sectional view taken on the line llll0 on Fig. 6 and looking in the direction of the arrows; and

Fig. 11 is an elevational the right in Fig. 1. v

This invention is related to printing machines and more especially to sheet feeding mechanisms view looking in from for use therewith, the present mechanism being particularly adapted for use with the printing machine disclosed in my copending application Serial No. 416,745, filed October 17, 1941.

When used in conjunction with such a machine, the sheet feeding unit is carried by a pair of side plates l8 and II, Figs. 1 and 2, which are tied together by rods l2, and the entire unit is mounted in cooperative relation with the table |3 of the printing machine. The unit is supported primarily by a brace H which is mounted at its upper end upon one of the tie rods l2 located near the lower edges of the side plates l8 and II, this brace being secured at its lower end to a bar I! which forms part of the framework of the printing machine with. which the new sheet-separating and sheet-feeding device is used. The lower end of the brace I4 is notched to seat on the bar l5 and is clamped to this bar by a clamping screw H which is threaded through a tapped opening in the brace I4 and which has a collar l5, Figs. 2 and 3, engaging the face of the bar 5 opposite the face of this the screw and collar |5 may be rotated to clamp or release the brace l4 as the case may be, a flat l9 being provided on the collar it to enable withdrawal of the brace H from the bar |5 when the screw I1 is turned to its release position.

For the purpose of accurately locating the sheet feeding unit relative to the table l3 of the machine, blocks 28, Figs. 2 and 4, are secured to the side plates l8 and II and carry downwardly extending pins 2| which seat in sockets formed in a rail 22' on the frame of the printing machine. When the sheet feeding unit is thus assembled relative to the printing machine, an

idler gear 2|, Figs. 1, 4 and 11, rotatably mounted on a' stub shaft 22 secured .to the side plate I5 is meshed with a driving gear 23, Fig. 4, which is fast to a drive shaft 24 embodied in the main portion of the printing machine. The idler gear 2| serves to transmit power from the driving gear 23 to a shaft 28 that extends between and is journaled in the side plates I0 and II. The shaft 28 carries a gear 25 outwardly of the side plate II, and this gear 25 is meshed with a gear 21 that is rotatably mounted on a shaft 28 extending between and journaled in the side plates Ill and II.

The shaft 25 is constantly driven rotatively so long as the idler gear 2| is meshed with the driving gear 23, but the shaft 28 is intermittently driven by the gear 21 through the medium of a clutch mechanism generally designated 29, Figs. 1 and 4. This clutch is of the type disclosed in my copending application Serial No. 239,561, flied November 8, 1938, now Patent No. 2,265,133, patented December 9, 1941, and is adapted to afford driving connection between the gear 21 and the shaft 28 during one complete revolution of the gear 21, such rotation of the shaft 28 constituting a cycle of the sheet feeding unit. Briefly, this clutch 28 has a driving member in the form of a collar 30, Fig. l, which is secured to the hub of the gear 21, and a driven member or collar 3| which is slidably but non-rotatably mounted on the shaft 28 adjacent the collar 30. Springs 32 interposed between the driven collar 3| and another collar 33 pinned to the shaft 28 tend to urge complementary teeth on the collars 38 and 3| into engagement with each other. However, such engagement of these teeth is normally prevented by a cam plate 84, Figs. 4, 8 and 9, pivotally mounted at one end thereof on a stub shaft 35 extending outwardly from the side plate II, this cam plate being spring-urged into engagement with the lowermost edge of the driven collar 3|. As shown in the detail vie'w, Fig. 8, the plate 34 has a cam edge 38 terminating in a recess 81 formed in a shoulder near the free end of the plate 84, which cam surface 38 cooperates with a pin 38 ilxed in the collar 3| to effect disengagement of the clutch members as will be described presently, the pin 38 normally being seated in the recess 31. A roller 33 mounted on the cam plate 34 rides on the face of the gear 21, Fig. 1, to prevent lateral movement of the Plate 34.

Operation of the clutch 28 is effected by a solenoid 43, Figs. 1 and 4, supported on a bracket 44 secured to the outer face of the side plate A vertically extending arm 45 is pivotally conneeted at its lower end to the core 48 of the solenoid 43 and is urged by a spring 41 against the collars 30 and 3| adjacent the free end of the cam plate 34. A lug 48, Fig. 9, on the vertical arm 45 is disposed above the end of the cam plate 34 so that when the solenoid 43 is energized the arm 45 is retracted downwardly and the lug 48 engages and pivots the plate 34 into its brokenline position out of engagement with the pin 88 on the collar 3|. Thereupon the springs 32 urge the collar 3| axially along the shaft 28 into mesh with the collar 30, Fig. 1, and the shaft 28 commences to rotate with the gear 21. As the collar 3| is driven rotatively, the pin 38 thereon strikes the arm 45 and pivots this arm to disengage the lug 48 from the end of the cam plate 34, as indicated in broken lines in Fig. 9, causing this plate 34 to be restored into engagement with the periphery of the collar 3| even though the solenoid 43 may remain energized. As the shaft 28 approaches the end of a complete revolution, the pin 38 on the collar 3| rides along the cam surface 36 on the plate 34, Fig. 8, causing the collar 3| to become disengaged from the collar 30. The pin 38 then seats in the recess 31, bringing the shaft 28 to a stop at the completion of exactly 360. To insure seating of the pin 38 in the recess 31, a spring-urged cam follower 48a, Fig. 4, pivotally mounted on the stub shaft 35 cooperates with a cam 49 on the shaft 28, this cam having a sharp drop in which the follower 49a. seats at the end of the cycle.

A sheet receptacle or rack 58, Fig. 2, is attached in a suitable manner to the sheet feeding unit and contains a supply of sheets which in the present instance may constitute check forms.

The pack is supported upright at a slight angle to the vertical and the upper edges of the sheets extend above the rack 50. A suction feeding device withdraws the sheets consecutively from the rack 50 and introduces them to a sheet advancing means to be described hereinafter. This suction device comprises a sucker bar 5| which is rockably mounted in a suitable manner on the side plates l0 and ii this sucker bar extending transversely of the machine in juxtaposition to the upper end of the rack 50. The sucker bar 5| is hollow and communicates with an exhaust duct leading to a suction pump or the like (not shown). A plurality of nozzles 52, Figs. 2 and 6, are arranged in spaced relation on the sucker bar and are movable to and from engagement with the Figs. 2 and 5, is pivotally connected at one end thereof to a depending Portion of the sucker bar 5| and at its other end is pivoted to a shaft 8| journaled in the side plates l6 and. H, the two arms of the lever 53 being pivotally interconnected at the bend of this lever by a pin 53'. A roller 55 rotatably mounted on the pin 53' cooperates with a cam 56 fast on the aforesaid shaft 28, a spring 51 acting on one arm of the lever 53 to urge the roller 55 against the periphery of the cam 56. The cam 56 is generally of circular configuration andis provided with a drop and an adjoining dwell. When the lever 53 is in its nor-- mal position shown in Fig. 2, which position it assumes when the roller 55 is riding on the circular portion of the cam 56, the sucker bar 5| is then in its lowermost position. This sucker bar has a valve 66 provided with an operating arm 6| which cooperates with a pin 62 stationarily mounted on the tie rod 2 to which thebrace I4 is pivoted. The arm 6| engages the pin 62 whenever the sucker bar 5| assumes the lowermost position just referred to, and thereupon opens the valve 66 to destroy the suction in the nozzles 52.

When in the course ofv a cycle of operation of the sheet feeding unit the drop in the cam 56 moves opposite the roller 55, the spring 51 thereupon rocks the lever 53 clockwise (as viewed in Fig. 2) to raise the arm 6| of the valve 66 out of engagement with the stationary pin 62, thereby 3o restoring the suction in the nozzles 52, and to bring these nozzles-52 into engagement with the foremost sheet in the pack. The roller- 55 then rides up on the dwell of the cam 56, causing the sucker bar 5| to commence its return movement effecting withdrawal of a sheet froma rack 56.

When a sheet is withdrawn from the pack by the sucker bar, it is presented to a sheet advancing means which feeds the sheet toward suitable conveying means on the table I3 of the printing machine. Such sheet advancing means includes feed rollers 65, Figs. 1 and 2, which are mounted on the shaft 26 in spaced relation and are individually secured thereto by set screws 66. As the roller 55 rides onto the circular periphery of the cam 56, Fig. the nozzles 52 are moved so as topass below the periphery of the feed rollers 65 and the valve 66 is opened in the manner explained hereinabove to relieve the suction in the nozzles. Shortly prior to the time the suction is destroyed, however, the leading edge of the sheet is clamped against the feed rollers 65 by clamping rollers 61 and the sheet is frictionally advanced by the rollers 65 and 61 toward the table l3 of the printing machine. Preferably the central clamping roller 61 is knurled so that it may firmly grip the sheet to prevent slippage thereof. Y a

The clamping rollers 61 are secured to a shaft 68 which is journaled at its ends in adjustable bearings. 69, Fig. 7, carried by rockers 16 that are pivotally mounted on the shaft 26 inwardly of the side plates HI and respectively. The clamping rollers 61 are thuscapable of bodily movement about the shaft 26 as acenter and may beretractedslightlyto enable the leading edge of a sheet to be placed against the peripheries of the feed rollers 65 by the suction nozzles 52, whereuponthe clampingrollers 61 may be restored to press theleadingedge of, the sheet against the feedrollers65. Such-retraction and advance of the clamping rollers, 61 relative to the feed rollers 65 is effected bycams 1l, Figsnl and 2, mounted on the intermittently driven shaft 28, which cams cooperate with rollers 12 rotatably mounted on the rockers 16. Springs 13 are extended between anchors in the side plates l6 and II and the rockers 16 to urge the followers 12 into engagement with the 5 peripheries of the cams 1|, and as these cams are rotated the followers 12 drop into recesses in the cams 1| and the clamping rollers 61 are shifted into sheet engaging position. When the followers 6 12 ride onto the rises of the cams 1|. the clamping rollers 61 are retracted out of such sheet engaging position, this occurring Just before a new sheet is to be introduced into the bite of the feed rollers.

As shown in Fig. 7, the bearings 69 for the 15 shaft 68 are positioned in recesses in the rockers '16 and are movable therein toward and away from the shaft 26. A screw 16 extends upwardly from each bearing 69 through an opening in a strip 15 which bridges the aforesaid recess and is 20 secured to the rocker 16. A small compression spring 16 interposed betweeneach bearing 69 and strip 15 tends to urge the shaft 68 radially toward the shaft 26. A nut 11 is threaded on each screw 16 and is provided with teeth that cooperate 5 with teeth out into the strip 15 to afford a detent for adjusting the pressure with which the sheets are gripped by the clamping rollers 61.

Preferably the clamping rollers 61 are positively driven, and to this end a'gear 18, Fig. 1, on the shaft 68 is meshed with a gear 19 on'the shaft-26, the ratio of these gears being such that the clamping rollers 61 and feed rollers 65 are driven at substantially the same peripheral speed. It will be understood that sufllcient clearance exists between these gear teeth to enable proper adjust- 40 and hence several devices are provided in the present instance to insure separation of the shifts individually from the pack. One such means comprises fingers 86, Figs. 1 and 2, which are individually secured to the shaft 8| and are adapted to move into engagement with the sheets in the rack 56 to retain the sheets therein as the foremost sheet is being withdrawn by the nozzles 52, as many of these retaining fingers 86 being provided .on the shaft 8| as may be necessary to perform this function. Rocking movement is imparted to the shaft 8| by a cam 82, Fig. 11, on the shaft 28, which cam engages a follower 83 on a spring-urged rocker arm 84 on the shaft 8|,

whereby the fingers 86 are reciprocated in timed relation with the withdrawal of sheets from the pack. v 1

To further insure that the sheets are properly separated, air ducts 85, Figs. 1, 2, 5 and 6, are disposed adjacent the side edges of the pack of 66 sheets to direct blasts of air from both sides of the pack. against the edges of the sheets, thereby rufiling the sheets and facilitating separation of the foremost sheet from the pack. The ducts 85 are clamped to-a rod 86 carried by the side plates 85 I6 and II and are connected by flexible hosing 81, Fig. 1, to a pipe 88 supported on the side plate I this pipe communicating with a source of compressed air (not shown). v i

Still another device which aids to prevent feeding of more than one sheet at a time from the rack 56 is the stripper 96, Figs. 2 and 6, which is adjustably supported on the end of a lever arm 9| by means of a screw-and-slot connection. The arm 9| is pivotally mounted on a tie rod I2 76 near the top of the unit and is connected by a pin 02 and an eccentric'screw 03 to an arm 04 carrying a rbller 05 which rides on the periphery of a cam 90 on the shaft 20. A leaf spring I! fastened to the tie rod I2 bears against the head of the eccentric screw 03 to urge the roller against the cam 00. As this cam is rotated the stripper 00 is lowered and raised in timed relation with the withdrawal of sheets from the rack 50. The lower edge of the stripper plate 00 is serrated as indicated at 00, Fig.2, so that when the stripper 90 is lowered, the serrated edge 00 is eilective to comb out the sheets and thereby facilitate separation thereof. A pin 00 extending radially from the eccentric screw 0! enables .thls screwto be turned for accurately adjustingthe relative angularity of the arms 0i and 04.

There may be occasions when two or more sheets are simultaneously advanced by the sucker nozzles 52 into the bite of the rollers and 01, despite the action of the aforesaid sheet separation devices, and because of this I provide a safety device which responds under such circumstances to prevent the feeding of the sheets to the printing machine. As shown in Figs. 6 and 10, a disc I00 (not shown in Figs. 1 and 2) is rotatably mounted on the shaft adjacent a feed roller but out of alignment with the associated clamping roller 01. A rod IOI, Figs. 1, I and 10, extends between and is carried by the rockers I. which carry the shaft 08 on which the clamping rollers 61 are mounted. A bracket I02, Figs. 6 and 10, is secured to this rod MI, and adjacent this bracket a calipering shoe- I03 is' pivotally mounted on the rod IOI in alignment with the disc I00. The shoe I03 has an upwardly extending arm I04 which is connected by a spring I00 to the bracket I02. The spring I05 urges the arm I04 into engagement with the end of an adjusting screw I00 mounted in the bracket I02, whereby the separation of the shoe I03 and disc I00 may be accurately determined. The shoe I03 is so adjusted that a sumcient clearance is provided between it and the disc I00 to permit passage of a single sheet without any tendency to rotate the disc I00. However, if two or more sheets attempt to pass between the shoe I03 and the disc I00, there is a binding eilect and the disc I00 is rocked clockwise away from its normal position shown in Fig. 10, the shoe I03 being unable to yield because of the engagement of its arm I04 with the end of the screw I00.

An arm I01 attached to the disc I00 carries an arm I 00 which cooperates with a normally open switch I00 mounted on one of the lower tie rods I2. The contact springs of this switch normally urge the arm I00 in a direction to maintain the arm I0'I in engagement with the tie rod I2. However, when a double feed occurs to cause the disc I00 to rotate,-the arms I01 and I08 are shifted to bring about closure of the switch contacts I09, and thereupon a warning signal is given or a control operation may be effected such as by suspending operation of the sheet feeding unit or diverting the double out of the normal path of movement of the sheets.

There may be instances in which a sheet feeding unit is employed in condunction with a printing machine which is set up for multiplicate this respect by energizing the solenoid 40 under control of a timing switch in the main part of the machine, as explained in my aforesaid copending application Serial No. 418,745.

From the foregoing it is apparent that'I have provided a dependable apparatus for separating advantageous features.

and feeding sheets and which embodies several Thus, for instance, the provision of the electrically controlled, one-revolution clutch drive affords a flexible arrangement in which the cycles of operation of the sheet feeding unit may be selectively timed with relation to the operation of the printing machine. Moreover, it is not necessary that the idler gear 2| carried by the sheet feeding unit, and the driving gear 24 in the printing machine, occupy any particular rotative positions relative to each other when meshed. Other important features consist in the provision of the air blast ducts OI, the sheet retaining fingers l0 and the stripper 90, these elements in combination serving to insure proper separation of the sheets. The positive drive of the clamping rollers 01 and the knurled configuration of the central clamping roller 01 serve to minimize the possibility of slipto avail myself of such changes and alterations as fall within the purview of the following claims.

I claim:

1. In a device for separating and feeding sheets consecutively from a stack thereof disposed in said device, a feed roller, suction nozzles, means for moving said suction nozzles into engagement with the forwardmost sheet in the stack and for then moving said nozzles past the periphery of said feed roller to engage the sheet with said feed roller, a clamping roller, means for retractprinting operations, that is, where each sheet reing said clamping roller along the periphery of the feed roller to enable engagement of the sheet with said feed roller and for advancing said clamping roller along the periphery of the feed roller into position to clamp the sheet in engagement with said feed roller, a stripping member movable into engagement with the leading edges of the sheets in said stack and having a serrated edge for combing out said sheets and thereby facilitating separation of the forwardmost sheet from the stack by said nozzles, and means moving said stripper member to and from engagement with the stack in timed relation with the movement of said nozzles.

2. In a device for separating and feeding sheets consecutively from a stack thereof disposed in said device, a feed roller, suction nozzles, means for moving said suction nozzles into engagement with the forwardmost sheet inthe stack and for then moving said nozzles past the periphery of said feed roller to engage the sheet with said feed roller, a clamping roller, means for 'retracting said clamping roller to enable engagement of the sheet with said feed roller and for advancing said clamping roller into position to clamp the sheet in engagement with said feed roller, and means for calipering said sheets as they are fed between said feed and clamping rollers to thereby detect the passage of more than a single sheet at a time, said calipering means comprising an element rockably mounted coaxially of said feed roller in the path of travel of said sheets, a shoe positioned in alignment with said element, said element and said shoe having opposed arcuate surfaces between which the sheets pass, means for adjusting the clearance between said shoe and element whereby the passage of more than a single sheet at a time causes said element to be rocked, and means responding to such rocking movement of said element in a manner indicative of an abnormal condition in the feeding of the sheets.

3. In a device for separating and feeding sheets consecutively from a stack thereof disposed in said device, a drive shaft, a feed roller mounted on said drive shaft, suction nozzles, means for moving said suction nozzles into engagement with the forwardmost sheet in the stack and for then-moving said nozzles past the periphery of said feed roller to engage the sheet with said feed roller, a clamping roller opposed to said feed roller, means for retracting said clamping roller along the periphery of'the feed roller to enable engagement of said forwardmost sheet with said feed roller and for advancing said clamping roller along the periphery of the feed roller into position to clamp the sheet in engagement with said feed roller, means for relieving the suction in said nozzles subsequent to movement thereof past the periphery of said feed roller and subsequent to advancing of said clamping roller, and means interconnecting said clamping roller and said drive shaft for positively driving said clamping roller at substantially the same peripheral speed as said feed roller.

4. In a device for separating and feeding sheets consecutively from a stack thereof disposed in said device, a feed roller, suction nozzles, means for moving said suction nozzles into engagement with the forwardmost sheet in the stack and for then moving said nozzles past the periphery of said feed roller to engage the sheet with said feed roller, a clamping roller opposed to said feed roller, means for retracting said clamping roller to enable engagement of said forwardmost sheet with said feed roller and for advancing said clamping roller into position to clamp the sheet in engagement with said feed roller, means for directing a blast of air against the edges of the sheet in the stack to thereby ruiile out the sheets when said nozzles are advanced into engagement with the forwardmost sheet, a stripping member movable into engagement with the leading edges of the sheets in said stack and havinga serrated edge for combing out said sheets and thereby facilitating separation of the forwardmost sheet from the stack by said nozzles, and means moving said stripper member to and from engage ment with the stack intimed relation with the movement of said nozzles.

5. A device as set forth in claim 4, including a finger reciprocated in timed relation with the movement of said nozzles and engaging said stack to assist said stripping member in restraining movement of unwanted sheets from the stack.

6. In a device for separating and feeding sheets consecutively from a stack thereof disposed in said device, a drive shaft, a feed roller fast on said drive shaft, a member pivotally mounted on said drive shaft, a shaft joumaled in said member and extending parallel to said drive shaft, a clamping roller fixed to the second-named shaft in opposed relation to said feed roller, a cam shaft, means affording a driv; ing connection between said drive shaft and said cam shaft, suction nozzles, a cam on said cam shaft'for effecting movement of said nozzles into engagement with the forwardmost sheet in the stack and for then moving said nozzles past theperiphery of said feed roller to engage the sheet with said feed roller, another cam on said cam shaft for rocking said pivoted member to thereby effect retraction of said clamping roller circumferentially of said feed roller to enable said forwardmost sheet to engage said feed roller and.

for then advancing said clamping roller into position to clamp said sheet against said feed roller, and intermeshing gears on said drive shaft and said clamping roller shaft for positively driving said clamping roller at substantially the same peripheral speed as said feed roller.

'7. In a device for separating and feeding sheets consecutively from a stack thereof disposed in said device, a drive shaft, a feed roller fast on said drive shaft, a member pivotally mounted ,on said drive shaft, a shaft iournaled in said member and extending parallel to said drive shaft, a clamping roller fixed to the second-named shaft in opposed relation to said feed roller, a cam shaft, means affording a driving connection between said drive shaft and said cam-shaft and including a clutch operable whenactuated to effect a cycle of rotation of said cam shaft, an electinmagnet for intermittently actuating said clutch,

suction nozzles, a cam on said cam shaft for and for then advancing said clamping roller into position to clamp such sheet against said feed roller.

WALTER '1. GOILWI'I'ZIB. 

